Fix Broken STL File Online Free
Use Paramesh AI's free mesh cleaner at parameshai.com/clean. Upload your broken STL and it automatically fixes normals, removes degenerate faces, merges duplicate vertices, and fills holes. Download the repaired STL instantly. No signup required, no file size limits for basic repair.
Common STL problems
- Flipped normals — some faces point inward instead of outward
- Degenerate faces — triangles with zero area (collapsed edges)
- Non-manifold edges — edges shared by more than 2 faces
- Gaps and holes — missing faces in the surface
- Duplicate vertices — overlapping points that should be merged
How the free cleaner works
- Go to parameshai.com/clean
- Drop your STL file (or OBJ, PLY, 3MF)
- The cleaner runs automatically — no buttons to click
- See before/after stats: face count, vertex count, watertight check
- Download the cleaned STL
What it fixes
The cleaner uses trimesh's repair pipeline: normal consistency, degenerate face removal, vertex merging, and hole filling. It handles most common mesh defects from 3D printing slicers, CAD exports, and 3D scanning.